Source code for airflow.providers.apache.hive.transfers.hive_to_mysql
#
# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements. See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership. The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied. See the License for the
# specific language governing permissions and limitations
# under the License.
"""This module contains an operator to move data from Hive to MySQL."""
from __future__ import annotations
from collections.abc import Sequence
from tempfile import NamedTemporaryFile
from typing import TYPE_CHECKING
from airflow.models import BaseOperator
from airflow.providers.apache.hive.hooks.hive import HiveServer2Hook
from airflow.providers.mysql.hooks.mysql import MySqlHook
from airflow.utils.operator_helpers import context_to_airflow_vars
if TYPE_CHECKING:
from airflow.utils.context import Context
[docs]class HiveToMySqlOperator(BaseOperator):
"""
Moves data from Hive to MySQL.
Note that for now the data is loaded into memory before being pushed
to MySQL, so this operator should be used for smallish amount of data.
:param sql: SQL query to execute against Hive server. (templated)
:param mysql_table: target MySQL table, use dot notation to target a
specific database. (templated)
:param mysql_conn_id: source mysql connection
:param hiveserver2_conn_id: Reference to the
:ref:`Hive Server2 thrift service connection id <howto/connection:hiveserver2>`.
:param mysql_preoperator: sql statement to run against mysql prior to
import, typically use to truncate of delete in place
of the data coming in, allowing the task to be idempotent (running
the task twice won't double load data). (templated)
:param mysql_postoperator: sql statement to run against mysql after the
import, typically used to move data from staging to
production and issue cleanup commands. (templated)
:param bulk_load: flag to use bulk_load option. This loads mysql directly
from a tab-delimited text file using the LOAD DATA LOCAL INFILE command. The MySQL
server must support loading local files via this command (it is disabled by default).
:param hive_conf:
"""
[docs] template_fields: Sequence[str] = ("sql", "mysql_table", "mysql_preoperator", "mysql_postoperator")
[docs] template_ext: Sequence[str] = (".sql",)
[docs] template_fields_renderers = {
"sql": "hql",
"mysql_preoperator": "mysql",
"mysql_postoperator": "mysql",
}
def __init__(
self,
*,
sql: str,
mysql_table: str,
hiveserver2_conn_id: str = "hiveserver2_default",
mysql_conn_id: str = "mysql_default",
mysql_preoperator: str | None = None,
mysql_postoperator: str | None = None,
bulk_load: bool = False,
hive_conf: dict | None = None,
**kwargs,
) -> None:
super().__init__(**kwargs)
self.sql = sql
self.mysql_table = mysql_table
self.mysql_conn_id = mysql_conn_id
self.mysql_preoperator = mysql_preoperator
self.mysql_postoperator = mysql_postoperator
self.hiveserver2_conn_id = hiveserver2_conn_id
self.bulk_load = bulk_load
self.hive_conf = hive_conf
[docs] def execute(self, context: Context):
hive = HiveServer2Hook(hiveserver2_conn_id=self.hiveserver2_conn_id)
self.log.info("Extracting data from Hive: %s", self.sql)
hive_conf = context_to_airflow_vars(context)
if self.hive_conf:
hive_conf.update(self.hive_conf)
if self.bulk_load:
with NamedTemporaryFile() as tmp_file:
hive.to_csv(
self.sql,
tmp_file.name,
delimiter="\t",
lineterminator="\n",
output_header=False,
hive_conf=hive_conf,
)
mysql = self._call_preoperator(local_infile=self.bulk_load)
mysql.bulk_load(table=self.mysql_table, tmp_file=tmp_file.name)
else:
hive_results = hive.get_records(self.sql, parameters=hive_conf)
mysql = self._call_preoperator()
mysql.insert_rows(table=self.mysql_table, rows=hive_results)
if self.mysql_postoperator:
self.log.info("Running MySQL postoperator")
mysql.run(self.mysql_postoperator)
self.log.info("Done.")
def _call_preoperator(self, local_infile: bool = False) -> MySqlHook:
mysql = MySqlHook(mysql_conn_id=self.mysql_conn_id, local_infile=local_infile)
if self.mysql_preoperator:
self.log.info("Running MySQL preoperator")
mysql.run(self.mysql_preoperator)
self.log.info("Inserting rows into MySQL")
return mysql